-LRB- CNN -RRB- -- The 54 men and 14 boys rescued after being found chained this week at an Islamic religious school in Pakistan have been reunited with their families or placed in shelters , authorities said .

The group was discovered in an underground room with heavy chains linking them together .

The school , Al-Arabiya Aloom Jamia Masjid Zikirya , which also was a drug rehab clinic , is in Sohrab Goth , a suburb of Gadap in Karachi .

All 14 boys were returned to their families , senior police official Ahsanullah Marwat told CNN .

Of the adults , 47 had been released to their families , and seven were handed over to a shelter for the homeless , he said .

Three people who worked at the facility were arrested , but the four men who ran the place were still at large , Marwat said .

Officials said the facility was part madrassa and part drug-rehab facility , and the captives were chained at night apparently to prevent their escape .

`` The operation was successful , and we plan on continuing our work to ensure that places like this are shut down , '' Marwat said .

Many of the captives told police their families sent them there because they were recovering drug addicts . During the day , they worked and did religious studies .

But the future of the rescued children was unclear .

One woman told a local television station that she was willing to pay the police to keep her troublesome child . She said she would rather have the facility remain open , regardless of how it treated the children .

Many others , however , said they were in shock and disbelief over the allegations .

One man complained he was deep in debt after paying the school a large amount of money to board his son .

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Captive boys and men were rescued from an Islamic religious school in Pakistan

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They were reunited with their families this week

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The facility was a school and drug rehab clinic

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Authorities say they 're searching for the owners ; three others arrested at the facility